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Climate variability, climate change and water resource strategies for small municipalities Critical Urgent Serious Table 5: Working classification of drought (DWAF Northern Cape 2005) Almost no water available. Water is being transported. Nearest water is more than 1km away. Water restrictions have been implemented. Expected to be critical in 2-3 months Water is available but resource is under stress. Water levels have dropped considerably. Expect to be urgent in 2-3 months 3.2 Overview of Northern Cape demand The urban and rural domestic water requirements only make up 4% of the total demand. The urban demand is generally concentrated along the main stem Orange River as a result of agriculture or at places such as Port Nolloth and Springbok due to mining. The rural communities are widespread and are mostly reliant on groundwater (V3 Consulting & WRP 2002). In 2000, the Northern Cape Province supply versus demand ratio illustrated the water vulnerability that exists in the province by effectively recording an undersupply of 8 million m 3 . If the supply and demand are projected to 2025, the water balance stays constant. This is mainly due to the demographic projections for this Water Management Area, which show a steady decline in population over the next 25 years (DWAF 2004b). Despite this documented water shortage, a survey of the small towns in the Northern Cape revealed that over 90% of the respondents stated that they understood there to be no limit on their demand for water (Macroplan 2000). Table 6: Reconciliation of water requirements and availability for the year 2000 (million m³/a) (DWAF 2004b) Component/ Sub-area Local yield Transfers In 2 Local requirements Transfers out Balance 1 Orange ( 986) 2 035 989 60 0 Orange Tributaries 22 0 31 0 ( 9) Orange Coastal 3 6 8 0 1 Total for WMA ( 961) 2 035 1 028 54 ( 8) 1. Brackets around numbers indicate a negative balance. Surpluses are shown in the most upstream sub-area where they first become available. 2. Transfers into and out of sub-areas may include transfers between sub-areas as well as transfers between WMAs. The addition of the quantities transferred per sub-area does therefore not necessarily correspond to total transfers into and out of the WMA. Table 7: Reconciliation of water requirements and availability for the year 2025 base scenario (million m³/a) (after DWAF 2004b) Component/ Sub-area Local yield 1 Transfers in Local requirements 2 Transfers out Balance 3 Potential for development 4 Orange ( 981) 2 082 1 042 60 ( 1) 150 Orange Tributaries Orange Coastal 22 0 29 0 ( 7) 0 2 6 8 0 0 0 Total for WMA ( 957) 2 088 1 079 60 ( 8) 150 1. Based on existing infrastructure and infrastructure under construction in the year 2000. Also includes return flows resulting from a growth in requirements. 2. Based on normal growth in water requirements as a result of population growth and general economic development. Includes a 4 000 ha increase in irrigated farming land in the Orange subarea, which will require 60 million m³/a. 3. Brackets around numbers indicate a negative balance. 4. Based on construction of the Vioolsdrift Dam. 8
Climate variability, climate change and water resource strategies for small municipalities Current utilisation of groundwater in this area is approximately in balance with the sustainable abstraction yield from this source and no significant potential for further development exists (BKS (Pty) Ltd 2003). Demand issues such as increased water use, peak use, seasonal variability, poor demand side management, poor water use planning, poor conservation and water losses have in the past contributed to water shortages in the Northern Cape (van Dyk et al. 2005). Poor planning for emergencies and the lack of structured contingency plans has resulted in water shortages during times of rainfall variability. This resulted in approximately 25% of the towns in the Northern Cape over-utilising their sustainable groundwater resources in 2000 (see Figure 3). Most notable are Strydenburg, Van Wyksvlei, Kammieskroon, Britstown, Carnavon, Kheis, Kommagas Spoegrivier, Kenhardt and Buffelsrivier. Strydenburg, Van Wyksvlei and Kammieskroon are particularly vulnerable, using up to 180% of the recommended yield. Recent information indicates that Britstown is still using double the available yield from existing boreholes. Van Dyk recommends using 80% of the available sustainable yield to ensure that there are sufficient resources for future growth in demand as well as providing a buffer to drought periods. (van Dyk 2004). In addition, a predominant problem that occurs in most water scarce towns is that very little cooperation is received from residents with regards to water saving and change of water use patterns (Jooste 2005). The supply of water has become a political issue and elected councilors are reluctant to impose punitive measures on residents to curb the water demand. Currently in Sutherland a tension exists between inadequate supply verses the local demand for flush toilets. Instead, large sums of money are being sourced through the drought relief funding for locating new sources of water where yields have dropped or boreholes have dried up. Strydenburg Van Wyksvlei Kammieskroon Britstow n Carnarvon Kheis Kommagas Spoegrivier Towns Kenhardt Buffelsrivier Calvinia Garies Khubus Paulshoek Bulletrap Riemvasmaak Leliefontein Noupoort Karkams Total towns dependent on groundwater = 75 Number utilizing > 80% resource = 19 0 20 40 60 80 100 120 140 160 180 200 % resource utilized Figure 3: Groundwater resource utilization in 2000 (van Dyk et al. 2005) It is not clear to local authorities whose responsibility it is to plan for drought conditions – local or national government, water services authorities or providers, or the water catchment management authorities. Water resource planning is generally not a priority until water supplies are strained due 9
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